α-Fe_2O_3烧结体气敏器件

研究了用共沉淀法制备的α-Fe_2O_3粉体制成的烧结体型气敏器件的性能。采用X射线衍射、电子扫描电镜、能谱方法对α-Fe_2O_3超细粉体和烧结体的结构和成份进行了分析和观察。     

基于离散曲率熵的徘徊行为检测

针对公共重点区域的智能监视问题,提出了一种新的徘徊行为异常检测方法。该方法利用视频目标跟踪算法得到可疑行人的运动轨迹,通过曲线拟合对运动目标的离散点轨迹进行平滑,计算离散点的离散曲率,计算感兴趣区域内运动目标轨迹点的离散曲率的熵及方差,通过离散熵阈值比较进行徘徊行为判断,该方法只需计算运动目标的轨迹,无需建立样本库,实验证明了该方法的有效性、实时性。     

茂金属催化剂与钛系催化剂聚乙烯滚塑料结构与性能研究

采用GPC、13C NMR、SSA、落锤冲击试验、耐环境应力开裂试验分析研究茂金属催化剂和钛系催化剂PE滚塑料的结构与性能.结果 表明:相对钛系催化剂滚塑料PE-2,茂金属催化剂滚塑料mPE-1的PD较窄、分子链支化点少,易形成较厚片晶,片晶厚度分布均匀,力学性能佳;优异的结构性能,使茂金属催化剂滚塑料mPE-1具有优...     

焦石坝页岩气储层黏土组分特征及其体积分数计算

黏土矿物是焦石坝构造页岩气储层的重要组成部分,其特征及体积分数对页岩气藏的开发效果有着较大影响。文中结合区域地质特征,分析黏土矿物体积分数变化趋势及其与有机质之间的关系,定性认识黏土矿物间孔,建立测井计算模型,定量计算黏土矿物及其组分体积分数。实践证明,页岩气储层中黏土矿物总量较低,且与脆性矿物体积分数具有"镜面"特征,测井计算模型能够较为准确地计算出黏土矿物绝对体积分数。该方法在焦石坝构造五峰组—龙马溪组页岩气储层评价中,取得良好应用效果。     

POM/TPU/改性纳米ZnO复合材料的结晶与力学性能研究

采用机械共混法和纳米ZnO表面偶联剂改性技术,制备了聚甲醛(POM)/热塑性聚氨酯(TPU)/改性纳米ZnO复合材料,并借助偏光显微镜(PLM)、差示扫描量热仪(DSC)和X射线衍射仪(XRD)分析了复合材料的结晶形态和结晶性能,研究了改性纳米ZnO用量对POM/TPU/改性纳米ZnO复合材料力学性能的影响。结果表明:改性纳米ZnO在体系中起到一定的异相成核作用,促进了POM的结晶,并使得POM球晶细化;当改性纳米ZnO用量为0.3%时,复合材料具有最佳综合力学性能。     

MgSO4—H2O体系高温结晶动力学研究

研究了１８０℃,硫酸镁的浓度为２０％的过饱和溶液的结晶动力学规律。结果表明,该体系只析出一水硫酸镁一种固相,利用优化配合Ｒｕｎｇｅ－Ｋｕｔｔａ微分方程组数值解法对实验数据进行处理,拟合得到结晶过程的动力学方程为：－ｄＣ／ｄｔ＝０．１１８,结晶过程受晶体生长控制。     

连续液柱流自由表面非平衡绝热蒸发

分析连续液柱流自由表面绝热蒸发过程并进行了数值模拟,获得了汽液界面温度及蒸发通量分布规律。结果显示表面非平衡蒸发过程速率仅为按热力学平衡条件下最大理论计算量的20%,并且受液柱内部向自由表面传热控制。表面蒸发过程迅速衰减,当x/L=0.5,表面释放的蒸发热与液柱内部过热量之比水ηx(蒸发进程)仅为0.25,蒸发进程已接近尾声,揭示了强化液柱表面更新是强化该过程的主要因素。本模型计算结果得到了单液柱流绝热真空蒸发实验数据的验证,蒸发速率模拟值与实验值相对误差小于10%。     

An outlier mining algorithm based on constrained concept lattice

Traditional outlier mining methods identify outliers from a global point of view. These methods are inefficient to find locally biased data points (outliers) in low dimensional subspaces. Constrained concept lattices can be used as an effective formal tool for data analysis because constrained concept lattices have the characteristics of high constructing efficiency, practicability and pertinency. In this paper, we propose an outlier mining algorithm that treats the intent of any constrained concept lattice node as a subspace. We introduce sparsity and density coefficients to measure outliers in low dimensional subspaces. The intent of any constrained concept lattice node is regarded as a subspace, and sparsity subspaces are searched by traversing the constrained concept lattice according to a sparsity coefficient threshold. If the intent of any father node of the sparsity subspace is a density subspace according to a density coefficient threshold, then objects contained in the extent of the sparsity subspace node are considered as bias data points or outliers. Our experimental results show that the proposed algorithm performs very well for high red-shift spectral data sets.     

柴油机燃油系统故障诊断仪

叙述了柴油机燃油系统故障诊断仪的基本组成和工作原理，重点介绍专家智能诊断系统的构成以及利用燃油压力波形模拟模式识别和进行故障诊断的方法。     

Integrated design method considering closed-loop stability for the slider-crank mechanism

The slider-crank mechanism is a transmission mechanism extensively used in engineering practice. It is necessary to use the control system for getting a satisfactory trajectory. So the mechanism design is composed of two parts, structural design and control design. These two parts impact each other and are tightly coupled, and the separate design can not obtain the best performance. Hence integrated design is imperative. By making use of the Lyapunov function, an integrated design considering stability is proposed in this paper, seeing that stability is the most basic requirements of a closed-loop system. Simulation results show that this method can effectively carry out the mechanism design, reduce the body weight, optimize mechanism performance and save the design cost simultaneously.